/**
 * md5
 */
export class Md5Utils {
    /*
   * A JavaScript implementation of the RSA Data Security, Inc. MD5 Message
   * Digest Algorithm, as defined in RFC 1321.
   * Version 1.1 Copyright (C) Paul Johnston 1999 - 2002.
   * Code also contributed by Greg Holt
   * See http://pajhome.org.uk/site/legal.html for details.
   */

    /*
     * Add integers, wrapping at 2^32. This uses 16-bit operations internally
     * to work around bugs in some JS interpreters.
     */
    private static safeAdd(x: number, y: number) {
        let lsw = (x & 0xFFFF) + (y & 0xFFFF)
        let msw = (x >> 16) + (y >> 16) + (lsw >> 16)
        return (msw << 16) | (lsw & 0xFFFF)
    }

    /*
     * Bitwise rotate a 32-bit number to the left.
     */
    private static rol(num: number, cnt: number) {
        return (num << cnt) | (num >>> (32 - cnt))
    }

    /*
     * These functions implement the four basic operations the algorithm uses.
     */
    private static cmn(q: number, a: number, b: number, x: number, s: number, t: number) {
        return Md5Utils.safeAdd(Md5Utils.rol(Md5Utils.safeAdd(Md5Utils.safeAdd(a, q), Md5Utils.safeAdd(x, t)), s), b)
    }
    private static ff(a: number, b: number, c: number, d: number, x: number, s: number, t: number) {
        return Md5Utils.cmn((b & c) | ((~b) & d), a, b, x, s, t)
    }
    private static gg(a: number, b: number, c: number, d: number, x: number, s: number, t: number) {
        return Md5Utils.cmn((b & d) | (c & (~d)), a, b, x, s, t)
    }
    private static hh(a: number, b: number, c: number, d: number, x: number, s: number, t: number) {
        return Md5Utils.cmn(b ^ c ^ d, a, b, x, s, t)
    }
    private static ii(a: number, b: number, c: number, d: number, x: number, s: number, t: number) {
        return Md5Utils.cmn(c ^ (b | (~d)), a, b, x, s, t)
    }

    /*
     * Calculate the MD5 of an array of little-endian words, producing an array
     * of little-endian words.
     */
    private static coreMD5(x: any) {
        let a = 1732584193
        let b = -271733879
        let c = -1732584194
        let d = 271733878

        for (let i = 0; i < x.length; i += 16) {
            let olda = a
            let oldb = b
            let oldc = c
            let oldd = d

            a = Md5Utils.ff(a, b, c, d, x[i + 0], 7, -680876936)
            d = Md5Utils.ff(d, a, b, c, x[i + 1], 12, -389564586)
            c = Md5Utils.ff(c, d, a, b, x[i + 2], 17, 606105819)
            b = Md5Utils.ff(b, c, d, a, x[i + 3], 22, -1044525330)
            a = Md5Utils.ff(a, b, c, d, x[i + 4], 7, -176418897)
            d = Md5Utils.ff(d, a, b, c, x[i + 5], 12, 1200080426)
            c = Md5Utils.ff(c, d, a, b, x[i + 6], 17, -1473231341)
            b = Md5Utils.ff(b, c, d, a, x[i + 7], 22, -45705983)
            a = Md5Utils.ff(a, b, c, d, x[i + 8], 7, 1770035416)
            d = Md5Utils.ff(d, a, b, c, x[i + 9], 12, -1958414417)
            c = Md5Utils.ff(c, d, a, b, x[i + 10], 17, -42063)
            b = Md5Utils.ff(b, c, d, a, x[i + 11], 22, -1990404162)
            a = Md5Utils.ff(a, b, c, d, x[i + 12], 7, 1804603682)
            d = Md5Utils.ff(d, a, b, c, x[i + 13], 12, -40341101)
            c = Md5Utils.ff(c, d, a, b, x[i + 14], 17, -1502002290)
            b = Md5Utils.ff(b, c, d, a, x[i + 15], 22, 1236535329)

            a = Md5Utils.gg(a, b, c, d, x[i + 1], 5, -165796510)
            d = Md5Utils.gg(d, a, b, c, x[i + 6], 9, -1069501632)
            c = Md5Utils.gg(c, d, a, b, x[i + 11], 14, 643717713)
            b = Md5Utils.gg(b, c, d, a, x[i + 0], 20, -373897302)
            a = Md5Utils.gg(a, b, c, d, x[i + 5], 5, -701558691)
            d = Md5Utils.gg(d, a, b, c, x[i + 10], 9, 38016083)
            c = Md5Utils.gg(c, d, a, b, x[i + 15], 14, -660478335)
            b = Md5Utils.gg(b, c, d, a, x[i + 4], 20, -405537848)
            a = Md5Utils.gg(a, b, c, d, x[i + 9], 5, 568446438)
            d = Md5Utils.gg(d, a, b, c, x[i + 14], 9, -1019803690)
            c = Md5Utils.gg(c, d, a, b, x[i + 3], 14, -187363961)
            b = Md5Utils.gg(b, c, d, a, x[i + 8], 20, 1163531501)
            a = Md5Utils.gg(a, b, c, d, x[i + 13], 5, -1444681467)
            d = Md5Utils.gg(d, a, b, c, x[i + 2], 9, -51403784)
            c = Md5Utils.gg(c, d, a, b, x[i + 7], 14, 1735328473)
            b = Md5Utils.gg(b, c, d, a, x[i + 12], 20, -1926607734)

            a = Md5Utils.hh(a, b, c, d, x[i + 5], 4, -378558)
            d = Md5Utils.hh(d, a, b, c, x[i + 8], 11, -2022574463)
            c = Md5Utils.hh(c, d, a, b, x[i + 11], 16, 1839030562)
            b = Md5Utils.hh(b, c, d, a, x[i + 14], 23, -35309556)
            a = Md5Utils.hh(a, b, c, d, x[i + 1], 4, -1530992060)
            d = Md5Utils.hh(d, a, b, c, x[i + 4], 11, 1272893353)
            c = Md5Utils.hh(c, d, a, b, x[i + 7], 16, -155497632)
            b = Md5Utils.hh(b, c, d, a, x[i + 10], 23, -1094730640)
            a = Md5Utils.hh(a, b, c, d, x[i + 13], 4, 681279174)
            d = Md5Utils.hh(d, a, b, c, x[i + 0], 11, -358537222)
            c = Md5Utils.hh(c, d, a, b, x[i + 3], 16, -722521979)
            b = Md5Utils.hh(b, c, d, a, x[i + 6], 23, 76029189)
            a = Md5Utils.hh(a, b, c, d, x[i + 9], 4, -640364487)
            d = Md5Utils.hh(d, a, b, c, x[i + 12], 11, -421815835)
            c = Md5Utils.hh(c, d, a, b, x[i + 15], 16, 530742520)
            b = Md5Utils.hh(b, c, d, a, x[i + 2], 23, -995338651)

            a = Md5Utils.ii(a, b, c, d, x[i + 0], 6, -198630844)
            d = Md5Utils.ii(d, a, b, c, x[i + 7], 10, 1126891415)
            c = Md5Utils.ii(c, d, a, b, x[i + 14], 15, -1416354905)
            b = Md5Utils.ii(b, c, d, a, x[i + 5], 21, -57434055)
            a = Md5Utils.ii(a, b, c, d, x[i + 12], 6, 1700485571)
            d = Md5Utils.ii(d, a, b, c, x[i + 3], 10, -1894986606)
            c = Md5Utils.ii(c, d, a, b, x[i + 10], 15, -1051523)
            b = Md5Utils.ii(b, c, d, a, x[i + 1], 21, -2054922799)
            a = Md5Utils.ii(a, b, c, d, x[i + 8], 6, 1873313359)
            d = Md5Utils.ii(d, a, b, c, x[i + 15], 10, -30611744)
            c = Md5Utils.ii(c, d, a, b, x[i + 6], 15, -1560198380)
            b = Md5Utils.ii(b, c, d, a, x[i + 13], 21, 1309151649)
            a = Md5Utils.ii(a, b, c, d, x[i + 4], 6, -145523070)
            d = Md5Utils.ii(d, a, b, c, x[i + 11], 10, -1120210379)
            c = Md5Utils.ii(c, d, a, b, x[i + 2], 15, 718787259)
            b = Md5Utils.ii(b, c, d, a, x[i + 9], 21, -343485551)

            a = Md5Utils.safeAdd(a, olda)
            b = Md5Utils.safeAdd(b, oldb)
            c = Md5Utils.safeAdd(c, oldc)
            d = Md5Utils.safeAdd(d, oldd)
        }
        return [a, b, c, d]
    }

    /*
     * Convert an array of little-endian words to a hex string.
     */
    private static binl2hex(binarray: Array<any>) {
        let hex_tab = "0123456789abcdef"
        let str = ""
        for (let i = 0; i < binarray.length * 4; i++) {
            str += hex_tab.charAt((binarray[i >> 2] >> ((i % 4) * 8 + 4)) & 0xF) +
                hex_tab.charAt((binarray[i >> 2] >> ((i % 4) * 8)) & 0xF)
        }
        return str
    }

    /*
     * Convert an array of little-endian words to a base64 encoded string.
     */
    private static binl2b64(binarray: Array<any>) {
        let tab = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
        let str = ""
        for (let i = 0; i < binarray.length * 32; i += 6) {
            str += tab.charAt(((binarray[i >> 5] << (i % 32)) & 0x3F) |
                ((binarray[i >> 5 + 1] >> (32 - i % 32)) & 0x3F))
        }
        return str
    }

    /*
     * Convert an 8-bit character string to a sequence of 16-word blocks, stored
     * as an array, and append appropriate padding for MD4/5 calculation.
     * If any of the characters are >255, the high byte is silently ignored.
     */
    private static str2binl(str: string) {
        var nblk = ((str.length + 8) >> 6) + 1 // number of 16-word blocks
        var blks = new Array(nblk * 16)
        for (var i = 0; i < nblk * 16; i++) blks[i] = 0
        for (var i = 0; i < str.length; i++)
            blks[i >> 2] |= (str.charCodeAt(i) & 0xFF) << ((i % 4) * 8)
        blks[i >> 2] |= 0x80 << ((i % 4) * 8)
        blks[nblk * 16 - 2] = str.length * 8
        return blks
    }

    /*
     * Convert a wide-character string to a sequence of 16-word blocks, stored as
     * an array, and append appropriate padding for MD4/5 calculation.
     */
    private static strw2binl(str: string) {
        var nblk = ((str.length + 4) >> 5) + 1 // number of 16-word blocks
        var blks = new Array(nblk * 16)
        for (var i = 0; i < nblk * 16; i++) blks[i] = 0
        for (var i = 0; i < str.length; i++)
            blks[i >> 1] |= str.charCodeAt(i) << ((i % 2) * 16)
        blks[i >> 1] |= 0x80 << ((i % 2) * 16)
        blks[nblk * 16 - 2] = str.length * 16
        return blks
    }

    /*
     * External interface
     */
    public static hexMD5(str: string) { return Md5Utils.binl2hex(Md5Utils.coreMD5(Md5Utils.str2binl(str))) }
    public static hexMD5w(str: string) { return Md5Utils.binl2hex(Md5Utils.coreMD5(Md5Utils.strw2binl(str))) }
    public static b64MD5(str: string) { return Md5Utils.binl2b64(Md5Utils.coreMD5(Md5Utils.str2binl(str))) }
    public static b64MD5w(str: string) { return Md5Utils.binl2b64(Md5Utils.coreMD5(Md5Utils.strw2binl(str))) }
    /* Backward compatibility */
    public static calcMD5(str: string) { return Md5Utils.binl2hex(Md5Utils.coreMD5(Md5Utils.str2binl(str))) }

}